On Tuesday, smoke from wildfires raging in Alberta descended over Calgary, the province’s largest city. Air pollution climbed to double the level considered hazardous, while the thick haze gave off an acrid smell, glowed orange and reduced visibility to half a mile.
As many as 150 active fires are burning across Alberta and British Columbia. In Calgary, about 300 miles from some of the largest blazes, the smoke settled near the ground. Now, the high-altitude winds of the jet stream are carrying this smoke into the Lower 48 states.
Scenes in Calgary were reminiscent of Seattle last summer and San Francisco in 2020 as wind currents blew smothering wildfire smoke into those population centers, compromising air quality.
The current fire situation
A provincial state of emergency remains in effect for Alberta as a result of wildfires concentrated in the northern half of the province. Mandatory evacuations were ordered Tuesday for the town of Swan Hills, about 100 miles northwest of Edmonton, Alberta, the latest population center to be threatened by flames that have already burned twice the normal annual acreage across the region.
Wildfires that have been burning for weeks in western Canada were initially set off by lightning storms in early May. Although firefighters gained a brief upper hand last week, the latest round of record heat and abnormally dry conditions intensified the blazes while also fueling new ones.
Smoke has been flooding the skies of Canada and the United States off and on throughout May, with the most impressive pulse arriving in recent days.
Smoke on the move
As a cold front passed Calgary on Tuesday morning, it opened the gates for a torrent of smoke to surge southward. The air-quality index vaulted from 46 (good) at 5 a.m. to over 500 (very hazardous) by 10 a.m.
“At this range the breathing and health of all individuals is impacted,” meteorologist Jayson Prentice wrote on Twitter.
Some air-quality readings in the area at times surpassed 600, essentially off the charts.
Areas of thick smoke and poor air quality remained entrenched across British Columbia, Alberta and Saskatchewan on Wednesday morning.
At high altitudes, the roaring winds of the jet stream have been transporting the smoke from Alberta into the United States in recent weeks — extending from the Northern Rockies to the East Coast. That’s continuing at present. In parts of Montana, including Glasgow, the smoke was thick enough Wednesday to require a dense-smoke advisory through the evening from the National Weather Service.
The smoke reached as far east as the Mid-Atlantic on Wednesday morning, with a smoky hazy blotting the rising sun in D.C.
Fires continue to flare
Fires have been flickering in parts of western Canada for several weeks now. While May is often the peak fire season in Alberta, the fire activity this year is near historic levels.
The combination of drought and abnormally warm conditions has helped fuel all of the flare-ups. Drought has been ongoing in parts of Alberta and Saskatchewan since late 2020, although its location and intensity have shifted around somewhat. Drought currently covers an expansive part of Canada from British Columbia to Manitoba.
The invasion of smoke is also seemingly part of a recent trend. Scott Dippel, a reporter with the Canadian Broadcasting Corp. in Calgary, shared the graph below showing a sharp ramp-up in the number of hours with smoke in Calgary in recent years:
If you are thinking wildfire smoke is becoming a regular part of Calgary's weather, you are correct. pic.twitter.com/HQKuZoLoYv— Scott Dippel (@CBCScott) May 16, 2023
Current fire activity could be a harbinger of a long summer.
Temperatures will continue to run about 10 to 20 degrees (5 to 11 Celsius) above normal in the region through early next week, before returning nearer average for a time, when some needed rain may also fall. But, thereafter, unusually warm weather may attempt a return.